Stacking an External Boost Controller on top of COBB for 21+ psi non-intrusively!

This discussion only pertains to tuning large than stock frame turbos. It does not apply to stock turbos, or hybrid turbos such as RB, Vargas Stage 1 or 2, ASR or TD so let's leave those out of this thread.

So, here we go, short and sweet hopefully...

Tuning with COBB to 21psi is what is currently supported in terms of max boost on I8A0S and IJE0S ROMs with alpha race code that is under development. Older MSD80 and MSD81 ROMs are limited to 18.5psi but the DME can be upgraded to the latest ROMs for them to be opened to 21psi as well. For 6ATs the Alpina TCU flash is required to push past 18.5psi and resolve certain torque intervention issues before tuning can be pushed past 18.5psi. If your car is older than 03/07 we're unable to currently tune your car reliably because of its older transmission computer.

If you're a 6MT or a 6AT with an Alpina TCU flash and running a fully custom aftermarket large turbo (turbos) kit, not one of the ones mentioned in the beginning, you'd be inclined to push boost higher and so would we. With Cobb right now the 21psi limit is currently in place and it won't budge until resolved. I don't know when it will be raised. I do know it is being worked on and it will come eventually.

In the meantime, we need to find a suitable external boost controller that doesn't hijack the CANBus

Current JB4/Procede as boost controllers:

Both currently use CANBus integration to make boost control work the way it does. My comfort level is low to none using them currently out-of-box as they take away ability to log some of the critical engine parameters only available on the AP. We lose visibility into timing corrections/knock across cylinders 2 through 6. Relying on just cylinder 1 timing for me is unacceptable when we can simply see the whole picture when the AP is plugged in. This is also the reason today we reject tuning any cars that stack on top of Cobb for meth or what have you.

I am trying to keep things inside the DME as much as possible, preserving all the critical logging while being able to go past 21psi controllably.

From discussions with Rob Irish back when he was still with Cobb and Terry I know there's a way to move the JB4 to another CANBus node/channel to make it work along side the Cobb AP. This would allow for addressing the boost limit with the JB4 being a non-intrusive external boost controller while allowing for full visibility into the engine's inner workings that the AP so conveniently exposes.

@Terry@BMS , is a JB4 configuration of such nature possible? If not, can the JB4 be moved over so critical Cobb AP datalogging isn't lost by plugging in the JB4 and the two can work in harmony forever Same goes to the procede camp as procede is already on Vargas' car as his customer already owned that tune prior to getting this work done (but I think I know the answer there already).

So boost becomes the bottleneck with S3 ST/TT turbos? At what power levels are being achieved with 21PSI generally with pump, pump+meth, pump+meth+E85? Are those turbos below their operating efficiency? I'm trying to understand the need for over 21PSI but the obvious answer is more power, like always.

Any good N54 boost control scheme will need CAN access to work properly.

The JB4 can be moved to another port but the DME can only spit out so many sample points per second. The JB4 requires at least 10hz. We've had customers who tried to run the JB4 with the P3 vent gauge which also uses CAN data only to find out it reduced the sample points returned to the JB4. So I'm not sure it's very viable.

It would be nice to get cyl 2-6 logging in the JB4 but I don't quite have all the information I'd need to do that currently. The JB4 can log the knock sensors directly but that data is a bit harder to interpret.

If you just want a crap way of doing it using something like a JB+ to introduce a fixed load offset might work. It could be programmed to always return say 80% or 90% of the actual load to the DME. Meaning your old ~21psi would actually be ~26psi. The JB+ would need to also be programmed to work with the N20 3.5 bar sensor as well of course.

It is the sole responsibility of the purchaser and installer of any BMS part to employ the correct installation techniques required to ensure the proper operation of BMS parts, and BMS disclaims any and all liability for any part failure due to improper installation or use. It is the sole responsibility of the customer to verify that the use of their vehicle and items purchased comply with federal, state and local regulations. BMS claims no legal federal, state or local certification concerning pollution controlled motor vehicles or mandated emissions requirements. BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways. Please see http://www.burgertuning.com/emissions_info.html for more information on legal requirements related to use of BMS parts.

It is the sole responsibility of the purchaser and installer of any BMS part to employ the correct installation techniques required to ensure the proper operation of BMS parts, and BMS disclaims any and all liability for any part failure due to improper installation or use. It is the sole responsibility of the customer to verify that the use of their vehicle and items purchased comply with federal, state and local regulations. BMS claims no legal federal, state or local certification concerning pollution controlled motor vehicles or mandated emissions requirements. BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways. Please see http://www.burgertuning.com/emissions_info.html for more information on legal requirements related to use of BMS parts.

I understand your concern/desire, but it will just stall stg3 progress if this is a necessity .. at least stack with the current available options and develop your desired config in parallel.

Stacking without complete visibility into what the engine and timing are doing is not something D is comfortable with, and I am not really either to be honest. These turbos support 425 HP each. That's 850 HP of flow potential, do I think we are going to see that. Prob not, but we will see how much we can get, doing so without being able to see everything the engine is doing, is not really something I want to do on a customers car.

Stacking without complete visibility into what the engine and timing are doing is not something D is comfortable with, and I am not really either to be honest. These turbos support 425 HP each. That's 850 HP of flow potential, do I think we are going to see that. Prob not, but we will see how much we can get, doing so without being able to see everything the engine is doing, is not really something I want to do on a customers car.

So, it looks like we will have the pump 91 oct tune that we asked for. Looking forward to Tuesday and your dyno graphs

you've said before you were willing to pop the engine... let's tune this $#@!. You can run a diagnostic Cobb only at 21psi and make some assumptions from there. Plus we have Vishnu camp with X cars running strong. Don't turn it up at first and wait until customer or inhouse car is will to. Have a smooth running 600hp goal which is fairly conservative.

With these concerns the whole meth control subject is very important, and critical to use a piggy, so I don't think the JB+ is an option unless you had a meth controler and JB+, but this would be getting too complicated. You can be very conservative with the right meth control. There's tuning priorities, and I don't think full CAN visibility should be the highest priority at this point... yes, it would be nice though.

you've said before you were willing to pop the engine... let's tune this $#@!. You can run a diagnostic Cobb only at 21psi and make some assumptions from there. Plus we have Vishnu camp with X cars running strong. Don't turn it up at first and wait until customer or inhouse car is will to. Have a smooth running 600hp goal which is fairly conservative.

With these concerns the whole meth control subject is very important, and critical to use a piggy, so I don't think the JB+ is an option unless you had a meth controler and JB+, but this would be getting too complicated. You can be very conservative with the right meth control. There's tuning priorities, and I don't think full CAN visibility should be the highest priority at this point... yes, it would be nice though.

I never said anywhere I am willing to pop the engine on a customers car. If engines go they go, but tuning blind for the sake of numbers is not really how I do things. We will procede with what we can on 22.5 psi. Why this has been taken to the forums I really do not know.

Does the canbus even have enough bandwidth to log all knock/timing/etc etc at high rpm without the jb4? The answer is no, it doesn't. The DME processes it all still but you won't see every minor change, logging every cylinder you'd be lucky to catch 1/10. Add some traction issues and that goes down farther. The canbus is a limited resource, but just because you can't see everything doesn't mean it's not functioning. Cars have made more power than this with much less computer controls.

That's my devil's advocate. The rational side of me agrees with you, at least for the initial tuning. Jb+ it to 26psi, if no knock, jb4 and good to go.

Oh don't be dramatic. The engine has proven well suited to high boost/power with the single turbo setups with proper octane via meth. This isn't new territory until you get over 650 wheel afaik. The DME will do its job fine if you give it the tools, which a nice manifold/turbos, Cobb, and good fuel does. Maybe there is a reason shiv stopped there.... and I doubt it's knock related. More likely ring lands or rods.

Keep up the good work either way, glad you're to the boost limits of the stock dme without issue! Awesome, awesome news. Great work dzenno, looking forward to more.

Oh don't be dramatic. The engine has proven well suited to high boost/power with the single turbo setups with proper octane via meth. This isn't new territory until you get over 650 wheel afaik. The DME will do its job fine if you give it the tools, which a nice manifold/turbos, Cobb, and good fuel does. Maybe there is a reason shiv stopped there.... and I doubt it's knock related. More likely ring lands or rods.

Keep up the good work either way, glad you're to the boost limits of the stock dme without issue! Awesome, awesome news. Great work dzenno, looking forward to more.

lmao take him your engine then tell him push it till it blows and then go buy yourself a knew one out of your pocket.

Oh don't be dramatic. The engine has proven well suited to high boost/power with the single turbo setups with proper octane via meth. This isn't new territory until you get over 650 wheel afaik. The DME will do its job fine if you give it the tools, which a nice manifold/turbos, Cobb, and good fuel does. Maybe there is a reason shiv stopped there.... and I doubt it's knock related. More likely ring lands or rods.

Keep up the good work either way, glad you're to the boost limits of the stock dme without issue! Awesome, awesome news. Great work dzenno, looking forward to more.

Trust me if this was my car, I wold not be worried at all. I don't my blowing up my $#@! in the name of science and progress. But the call to the customer, um hey yeah,cCar is running great, remember when I said we would be done tuning in a few weeks. Well your engine, had a "slight malfunction" might be a little longer, are not fun calls.

Lol, I can respect that! Just being difficult because I'm jealous you get to play with it all weekend, and reminding you guys that logs in Cobb are limited still, even if not as much without extra gadgetry on the canbus.

I am looking to use a proper external boost controller. JB+ is not a boost controller.

In terms of logging...regardless of what the CANBus provides in terms of refresh/polling frequency (procede and jb4 use the same) having the AP provide its additional logging channels we just get way more insight. I'm not willing to do away with that data just to be able to stack another 3-4psi on top and play the ignorance game on 5 cylinders. What I/you/them do on personal cars is very different from using someone else's car when it comes to tuning.

If the JB4 could be setup to do boost control in a non-intrusive way when it comes to the CANBus that'd be great that'd be my choice given the 21psi boost limit. We'd also have no issues custom tuning or recommending such a non-intrusive setup as it gives you the best of both worlds right now until another system can do it all in one place either through the DME or via a full standalone. At this point those are still unfortunately a pipe dream on this platform.

However we get it resolved it only helps everyone who is interested in this kit as it will push it into production that much faster if we dont have to wait for Cobb to take their months to get the boost tables done. Hopefully we can all work together for the good of the platform.

Well, there are only three of us that can tune it. Either Shiv, myself, or D. And we all have our own ways of doing things and requirements. For example for something as radical as this setup I would only want to tune it if it were on a car we own where we can control all the parameters and spend a lot of time with it. That gives us time to develop whatever we need to develop as the tuning dictates. Shiv, probably won't want to touch it as he has his muscle behind the FFTEC single turbo setup. But you can try him. And D has his own opinions and ways of wanting to handle things so he will need to sort that out on his own if he's the one doing the project for you.

It is the sole responsibility of the purchaser and installer of any BMS part to employ the correct installation techniques required to ensure the proper operation of BMS parts, and BMS disclaims any and all liability for any part failure due to improper installation or use. It is the sole responsibility of the customer to verify that the use of their vehicle and items purchased comply with federal, state and local regulations. BMS claims no legal federal, state or local certification concerning pollution controlled motor vehicles or mandated emissions requirements. BMS products labeled for use only in competition racing vehicles may only be used on competition racing vehicles operated exclusively on a closed course in conjunction with a sanctioned racing event, in accordance with all federal and state laws, and may never be operated on public roads/highways. Please see http://www.burgertuning.com/emissions_info.html for more information on legal requirements related to use of BMS parts.

Way to stick with your convictions… and now we wait… and wait… for stg 3 #s. Oh well it was a nice project.

Seriously DZ… you need to really rethink some of your approach IMO. CAN visibility shouldn’t be your only concern. You are thinking to tune with non-integrated meth control. How is meth flow during transitions, specifically a MT shift, or even stabbing the throttle? So, what’s more important the unknown in cyl timing or meth control. Unfortunately can’t have both now, and not so easy to config a standalone properly with the current hardware… hopefully ProEFI is taking this into account.

Tony, you are working with new tuner that has limited experience especially at higher HP… he knows he stuff to a point, but you may want to rethink who you will work with bring stg3 to the market. Can’t really market the hardware without results, and at this pace results won’t be too encouraging.

My opinion… getting too close to 100 rep points, so thought I needed an adjustment.

Way to stick with your convictions… and now we wait… and wait… for stg 3 #s. Oh well it was a nice project.

Seriously DZ… you need to really rethink some of your approach IMO. CAN visibility shouldn’t be your only concern. You are thinking to tune with non-integrated meth control. How is meth flow during transitions, specifically a MT shift, or even stabbing the throttle? So, what’s more important the unknown in cyl timing or meth control. Unfortunately can’t have both now, and not so easy to config a standalone properly with the current hardware… hopefully ProEFI is taking this into account.

Tony, you are working with new tuner that has limited experience especially at higher HP… he knows he stuff to a point, but you may want to rethink who you will work with bring stg3 to the market. Can’t really market the hardware without results, and at this pace results won’t be too encouraging.

My opinion… getting too close to 100 rep points, so thought I needed an adjustment.

Dzenno is incredibly knowledgeable, I'd trust him with my car any day. But I think he's been spoiled by the AP a little bit. You don't need that much data to tune a car, but it's safer no doubt, and easier to have it. I don't blame him in any decision he's made, it's the best way to handle the tuning given the options our platform has. But, given the lack of options getting over this hurdle, he'll have to either get creative, or change his perspective to a little more old school or open minded.

I will say this from experience, and I have some of it. If you intend to extract every horsepower from this kit on a stock block, you will have to break one. I'm sorry, there's really no getting around it. And it will happen suddenly, without warning, and not be anything related to knock if you're keeping the conditions in check. I have nothing to contribute here sorry for dragging things ot, it's a curse in this forum lol.

Way to stick with your convictions… and now we wait… and wait… for stg 3 #s. Oh well it was a nice project.

Seriously DZ… you need to really rethink some of your approach IMO. CAN visibility shouldn’t be your only concern. You are thinking to tune with non-integrated meth control. How is meth flow during transitions, specifically a MT shift, or even stabbing the throttle? So, what’s more important the unknown in cyl timing or meth control. Unfortunately can’t have both now, and not so easy to config a standalone properly with the current hardware… hopefully ProEFI is taking this into account.

Tony, you are working with new tuner that has limited experience especially at higher HP… he knows he stuff to a point, but you may want to rethink who you will work with bring stg3 to the market. Can’t really market the hardware without results, and at this pace results won’t be too encouraging.

My opinion… getting too close to 100 rep points, so thought I needed an adjustment.

I'm sure in your case anyone but Shiv and Procede would be inappropriate. Think out of the box Josh. Don't always be so negative dude

Way to stick with your convictions… and now we wait… and wait… for stg 3 #s. Oh well it was a nice project.

Seriously DZ… you need to really rethink some of your approach IMO. CAN visibility shouldn’t be your only concern. You are thinking to tune with non-integrated meth control. How is meth flow during transitions, specifically a MT shift, or even stabbing the throttle? So, what’s more important the unknown in cyl timing or meth control. Unfortunately can’t have both now, and not so easy to config a standalone properly with the current hardware… hopefully ProEFI is taking this into account.

Tony, you are working with new tuner that has limited experience especially at higher HP… he knows he stuff to a point, but you may want to rethink who you will work with bring stg3 to the market. Can’t really market the hardware without results, and at this pace results won’t be too encouraging.

My opinion… getting too close to 100 rep points, so thought I needed an adjustment.

Josh you sound very knowledgeable. Please point me to a couple of cars you have tuned that hold any weight in the N54 platform and hold or have broken in the past any of the HP, Torque, or timed records, I mean you must since you are so quick to point out that my tuner is not very experienced, yet holds quite a few. You can email me if you want to keep it off the forums. Thanks

We chose to Go with PTF meaning Jake and Dzenno simply because after talking with them, they were very knowledgeable and I really like where Cobb is going with the platform right now. I trust them explicitly with the tuning on this car. D is available to me quite literally 24 hours a day and many times he is like, lets tune, lets tune and I am super busy and have to wait. He is just as excited about the project as I am and he hasn't even got the ride in the car yet. Working with him is a pleasure and his wealth of N54 knowledge has helped me tremendously since my own N54 knowledge limited but growing daily. I will say It is quite a let down that Cobb were so quick to promise the boost limit would be removed and now say it will be months, but I do not regret the decision I made. Don't worry guys, 91 map should be done this weekend and we should be looking at numbers on Tuesday.

@dzenno@ProTUNING Freaks, what is preventing you from using a different MAP sensor and doing it all in the AP? Is there still a limit in the code that Cobb hasn't found that prevents it from happily processing higher boost while using the new MAP sensor?